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Figure 1. Map of Norway showing the positions sample collection
areas. Numbers correspond to numbers given in Table 1.
Figure 2. Box plot of the measured equatorial width (E) of
pollen. The box encloses the middle half of the data of the second and
third quartiles, the thick horizontal line is the median, and the
vertical lines show the range of data values in the first and fourth
quartiles. Extreme outliers are shown as open circles. Colors of boxes
refer to ploidy level (from Table 2). The inset box shows a plot of the
correlation between E and ploidy level. The correlation is 0.45.
Figure 3. Box plot of the measured polar length (P) of pollen.
The box encloses the middle half of the data of the second and third
quartiles, the thick horizontal line is the median, and the vertical
lines show the range of data values in the first and fourth quartiles.
Extreme outliers are shown as open circles. Colors of boxes refer to
ploidy level (from Table 2).
Figure 4. Box plot of the measured of the P/E ratio. The box
encloses the middle half of the data of the second and third quartiles,
the thick horizontal line is the median, and the vertical lines show the
range of data values in the first and fourth quartiles. Extreme outliers
are shown as open circles. Colors of boxes refer to ploidy level (from
Table 2) and vertical dotted lines mark different shapes of pollen
following Erdtman (1952).
Figure 5. Scanning electron microscopy (SEM) images pollen from
each specimen analysed in (1) polar view, (2) equatorial view, and (3)
close-up of pollen grain exine ornamentation. The scale bars are 2 µm.
Figure 6. The first two axes resulting from the Principal
Component Analysis (PCA) of pollen measurements (P and E) and the
calculated ratio (P/E) from this study. The ploidy levels (from Table 2)
are referred to in the different colors.
Figure 7. The first two resulting axes from the Principal
Component Analysis (PCA) of all pollen characters (as given in Table 3).
Different genera are marked in colors.
Figure 8. The calculated P/E ratio from measurements in this
study compared with several other studies. Colors of bars refer to the
data source.
Table 1. Species included in this study with origin, herbarium,
and collection numbers, date of collection, and endemism status. Numbers
in brackets are referring to Figure 1.
Table 2. DNA content with measured or given polyploidy levels.
* are taken from (Kurtto et al., 2018).
Table 3. Morphological characteristics of the pollen
surface interpreted from the SEM pictures in Figure 5.